package main

import (
	"fmt"
	"strings"
)

func main() {
	var s1 string
	s1 = "Hello World"

	fmt.Println(len(s1))
	fmt.Println(string(s1[2]))

	isContain := strings.Contains(s1,"H")
	fmt.Printf("%s中包含H：%v",s1,isContain)
}
